1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2010 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 /* 27 * Launch Java executables via exec(2). 28 * 29 * Java executables are platform-independent executable files 30 * based on the JAR file format. Executable JAR files contain a 31 * special 'extra field' header in the first file of the archive 32 * that marks the file as a true executable. The data in that field 33 * is used to pass additional run-time information to the Java VM. 34 * 35 * This handler looks for the appropriate magic number on the 36 * front of the file, checks that the JAR file is executable, then 37 * invokes the Java runtime environment to do the rest of the work. 38 */ 39 40 #include <sys/types.h> 41 #include <sys/proc.h> 42 #include <sys/vnode.h> 43 #include <sys/exec.h> 44 #include <sys/modctl.h> 45 #include <sys/cmn_err.h> 46 #include <sys/pathname.h> 47 48 /* 49 * These variables can be tweaked via /etc/system to allow prototyping 50 * and debugging. See PSARC/1997/123. 51 * 52 * Modified by PSARC/1999/012 to be Contract Private between Solaris and 53 * the Java Technology Group. It is expected that any future change to 54 * these variables be coordinated between the consolidations. 55 */ 56 #if defined(__sparc) 57 char *jexec = "/usr/java/jre/lib/sparc/jexec"; 58 #elif defined(__x86) 59 char *jexec = "/usr/java/jre/lib/i386/jexec"; 60 #else 61 #error "Unknown ISA" 62 #endif 63 char *jexec_arg = "-jar"; 64 65 /* 66 * ZIP/JAR file header information 67 */ 68 #define SIGSIZ 4 69 #define LOCSIG "PK\003\004" 70 #define LOCHDRSIZ 30 71 72 #define CH(b, n) (((unsigned char *)(b))[n]) 73 #define SH(b, n) (CH(b, n) | (CH(b, n+1) << 8)) 74 #define LG(b, n) (SH(b, n) | (SH(b, n+2) << 16)) 75 76 #define LOCNAM(b) (SH(b, 26)) /* filename size */ 77 #define LOCEXT(b) (SH(b, 28)) /* extra field size */ 78 79 #define XFHSIZ 4 /* header id, data size */ 80 #define XFHID(b) (SH(b, 0)) /* extract field header id */ 81 #define XFDATASIZ(b) (SH(b, 2)) /* extract field data size */ 82 #define XFJAVASIG 0xcafe /* java executables */ 83 84 /*ARGSUSED3*/ 85 static int 86 javaexec(vnode_t *vp, struct execa *uap, struct uarg *args, 87 struct intpdata *idatap, int level, long *execsz, int setid, 88 caddr_t execfile, cred_t *cred, int brand_action) 89 { 90 struct intpdata idata; 91 int error; 92 ssize_t resid; 93 vnode_t *nvp; 94 off_t xoff, xoff_end; 95 char lochdr[LOCHDRSIZ]; 96 struct pathname lookpn; 97 struct pathname resolvepn; 98 char *opath; 99 100 if (level) 101 return (ENOEXEC); /* no recursion */ 102 103 /* 104 * Read in the full local file header, and validate 105 * the initial signature. 106 */ 107 if ((error = vn_rdwr(UIO_READ, vp, lochdr, sizeof (lochdr), 108 0, UIO_SYSSPACE, 0, (rlim64_t)0, cred, &resid)) != 0) 109 return (error); 110 if (resid != 0 || strncmp(lochdr, LOCSIG, SIGSIZ) != 0) 111 return (ENOEXEC); 112 113 /* 114 * Ok, so this -is- a ZIP file, and might even be a JAR file. 115 * Is it a Java executable? 116 */ 117 xoff = sizeof (lochdr) + LOCNAM(lochdr); 118 xoff_end = xoff + LOCEXT(lochdr); 119 120 while (xoff < xoff_end) { 121 char xfhdr[XFHSIZ]; 122 123 if ((error = vn_rdwr(UIO_READ, vp, xfhdr, sizeof (xfhdr), 124 xoff, UIO_SYSSPACE, 0, (rlim64_t)0, cred, &resid)) != 0) 125 return (error); 126 if (resid != 0) 127 return (ENOEXEC); 128 if (XFHID(xfhdr) == XFJAVASIG) 129 break; 130 xoff += sizeof (xfhdr) + XFDATASIZ(xfhdr); 131 } 132 133 if (xoff >= xoff_end) 134 return (ENOEXEC); 135 136 /* 137 * Note: If we ever make setid execution work, we need to ensure 138 * that we use /dev/fd to avoid the classic setuid shell script 139 * security hole. 140 */ 141 if (setid) 142 return (EACCES); 143 144 /* 145 * Find and invoke the Java runtime environment on the file 146 */ 147 bzero(&idata, sizeof (intpdata_t)); 148 idata.intp = NULL; 149 idata.intp_name[0] = jexec; 150 idata.intp_arg[0] = jexec_arg; 151 if (error = pn_get(idata.intp_name[0], UIO_SYSSPACE, &lookpn)) 152 return (error); 153 pn_alloc(&resolvepn); 154 if (error = lookuppn(&lookpn, &resolvepn, FOLLOW, NULLVPP, &nvp)) { 155 pn_free(&resolvepn); 156 pn_free(&lookpn); 157 return (ENOEXEC); 158 } 159 opath = args->pathname; 160 args->pathname = resolvepn.pn_path; 161 /* don't free resolvepn until we are done with args */ 162 pn_free(&lookpn); 163 error = gexec(&nvp, uap, args, &idata, level + 1, execsz, execfile, 164 cred, EBA_NONE); 165 166 if (!error) { 167 /* 168 * Close this Java executable as the interpreter 169 * will open and close it later on. 170 */ 171 (void) VOP_CLOSE(vp, FREAD, 1, (offset_t)0, cred, NULL); 172 } 173 174 VN_RELE(nvp); 175 args->pathname = opath; 176 pn_free(&resolvepn); 177 return (error); 178 } 179 180 static struct execsw jexecsw = { 181 javamagicstr, 182 0, 183 4, 184 javaexec, 185 NULL 186 }; 187 188 static struct modlexec jmodlexec = { 189 &mod_execops, "exec for Java", &jexecsw 190 }; 191 192 static struct modlinkage jmodlinkage = { 193 MODREV_1, &jmodlexec, NULL 194 }; 195 196 int 197 _init(void) 198 { 199 return (mod_install(&jmodlinkage)); 200 } 201 202 int 203 _fini(void) 204 { 205 return (mod_remove(&jmodlinkage)); 206 } 207 208 int 209 _info(struct modinfo *modinfop) 210 { 211 return (mod_info(&jmodlinkage, modinfop)); 212 } 213